The .30-06 Springfield cartridge (pronounced "Thirty aught six") is a .308 inch (7.62 mm) caliber rifle cartridge, also known as the 7.62 x 63 mm, that was introduced as the standard cartridge of the United States Army in 1906.
It superseded the nearly identical .30-03 cartridge (introduced three years prior), but had a slightly shorter casing and a higher velocity spitzer bullet. The change to a pointed 'Spitzer' was in response to French and German developments during that time period. There were three main production runs of the round, that roughly correspond to large stocks built up during wars;the initial 30-06, the M1 ball and then the M2 ball.
The Springfield 1903 rifle, introduced alongside the earlier cartridge, was quickly modified to accept the .30-06. The .30-06 remained the US Army's main cartridge for nearly 50 years before it was finally replaced by the 7.62 x 51 mm with the official adoption of the M14 in 1954. However, the first M14s were not fielded until 1957, and the .30-06 remained in service into the 1970s, mainly as a machine gun cartridge.
It was used in the bolt-action M1903 Springfield, the semi-automatic M1 Garand and the Browning Automatic Rifle (BAR) as well as numerous machineguns. It served the United States in both World Wars and in the Korea, serving as the basis for dozens of commercial and wildcat cartridges. Its last major use by the US military was in Vietnam. The .30-06's power, combined with the ready availability of surplus firearms chambered for it, has made it a popular hunting cartridge. It is suitable for hunting large mammals such as deer, elk, and moose.
Performance
The .30-06 is a powerful round designed in an age when 1000 yard shots could be expected. In 1906, the original .30-06 cartridge consisted of a 150 grain flat base cupronickel jacketed bullet. During World War I, the United States military desired better long range performance out of machine guns and a streamlined, 172 grain, boat tail, cupronickel-jacketed bullet was used. The .30-06 cartridge with the 172 grain bullet was called the 'M1 Ball'. Later, the US military realized that M1 Ball was traveling beyond the safety limits of ranges constructed for the 1906 cartridge. Rather than engage in massive construction projects, it was decided to switch back to the original profile bullet.
A 150 grain flat base copper jacketed bullet was adopted and resulted in the creation of 'M2 Ball'. According to US Army Technical Manual 43-0001-27, M2 Ball specifications call for 2740 feet per second velocity (measured 78 feet from the muzzle). M2 Ball was the standard issue ammunition for use in US military service rifles until the retirement of the M1 Garand service rifle.
Commericially manufactured rifles chambered in .30-06 are popular for hunting. Current .30-06 factory ammuntion varies in bullet weight from as high as 220 grains down to 110 grains in solid bullets, and as low as 55 grains with the use of a sub-caliber bullet in a sabot. Loads are available with reduced velocity and pressure as well as increased velocity and pressure for stronger firearms. The .30-06 ranks as one of the most popular sporting cartridges in the world.
Ammunition types
- Ball, M1906
- This cartridge is used against personnel and unarmored targets, and can be identified by its unpainted bullet. The M1906 has an 150 grain projectile and flat base. Its jacket is a cupro-nickel alloy which was found to foul the bore quickly.
- Ball, M1
- The M1 has an 173 grain boat streamlined projectile designed for aerodynamic efficiency. Though it had a lower initial velocity, velocity and energy were greater at longer ranges due to its efficient shape.
- Ball, M2
- When M1 ammunition was found to travel beyond safety limits at Army ranges, the decision was made to switch back to the M1906 bullet shape with an improved gilding metal jacket to reduce metal fouling.
- Armor Piercing, M2.
- This cartridge is used against lightly armored vehicles, protective shelters, and personnel, and can be identified by its black bullet tip.
- Armor Piercing Incendiary, M14
- This cartridge is used, in place of the armor piercing round, against flammable targets. The tip of the bullet is colored with aluminum paint.
- Incendiary, M1.
- This cartridge is used against unarmored, flammable targets. The tip of the bullet is painted blue.
- Tracers M1 and M25
- These cartridges are for observing fire, signaling, target designation, and incediary purposes. The tips of the bullets are painted red for the M1 and orange for the M25.
- Blank, M1909.
- This cartridge is used to simulate rifle fire. The cartridge is identified by having no bullet, and by a cannelure in the neck of the case which is sealed by red lacquer.
- Rifle Grenade Cartridge, M3
- This cartridge is used with the grenade launcher to propel grenades. The cartridge has no bullet and the mouth is crimped.
- Dummy, M40
- This cartridge is used for training. The cartridge has six longitudinal corrugations and there is no primer.
- Match, M72
- This cartridge is used in marksmanship competition firing, and can be identified by the word "MATCH" on the head stamp.
Selected examples of United States Military firearms chambered for the .30-06 cartridge
- M1903 Springfield and variants, loading from stripper clips.
- Gatling gun, The U.S. Gatling guns were re-chambered for 30-06, the last round they would be changed over to before being declared obsolete and withdrawn from service.
- Model 1909 machine rifle, The Benet-Mercie light machine gun was chambered for 30-06.
- Chauchat, The US used a mix of Chauchauts in 30-06 and 8 mm lebel.
- Lewis gun The US used a limited amount of Lewis guns chambered in 30-06 in both WWI and WWII.
- M1917 Enfield, also loading from stripper clips. Despite its name was actually based on Mauser, not Enfield bolt.
- M1917 water-cooled and M1919 air-cooled machine guns, feeding from belts
- M1918 Browning Automatic Rifle, loading from detachable magazines.
- Marlin machine gun. Similar to the Colt-Browning machine gun ('Potato Digger'), but without 'digger' piston, and used mainly on aircraft.
- M1 Garand, loading in an en bloc clip
- M1941 Johnson, feeding from an internal rotary magazine
- Johnson M1941 LMG, feeding from magazine